Figure 1. (A) Chest X-ray on day 3 of conventional mechanical ventilation, demonstrating the development of relatively mild subcutaneous emphysema (red arrows) and mild pneumomediastinum (blue arrows). Note these findings are present despite the absence of pneumothorax. (B) Chest X-ray on conventional ventilation, just prior to transition to HFOV, demonstrating marked worsening of subcutaneous emphysema (red arrows) and pneumomediastinum. Fenestrated subcutaneous catheters (yellow arrows) placed bilaterally for evacuation of subcutaneous emphysema. Note there is still no pneumothorax. (C) Chest X-ray on day 6 of HFOV, just prior to transition back to conventional ventilation, demonstrating markedly improved subcutaneous emphysema (red arrows) and pneumomediastinum (blue arrows). Two fenestrated subcutaneous catheters remain in place.